The biographies of Zuckerberg aren't exactly spilling over with excited ­stories about the music he loved while a ­student at Harvard. But it's worth remembering that in, say, ­February 2004 there were just 650 people ­registered on Facebook. Today, there are well in excess of 500 million active users, who share everything – including the music they've loved for years, the music they've only just heard and the music they really want to hear next – with their friends. In reality, then, it is ­Zuckerberg's creation that is driving people towards new music. Of all the time spent on the internet in the US last year, 4.1% was on Google while 11.6% was on Facebook. This has only just begun.